200tdi overheating - Part 2 (I think!)

Hi all,

A while ago now I posted re my 200tdi, 150k miles running hot (3/4 way
accross on the gauge).

Upshot was that I replaced knackered radiator, thermostat and viscous
coupling. This made it so that the vehicle (90) would run all day at
about 3/4 of the temperature guage without rising when working hard.

This weekend the needle started to venture towards the red so Im back
pondering the options to return the needle to where it should be
(about 1/2 way).


I still have no signs of water in my oil or oil in my water. It
doesnt seem to use a drop of water (never have to top it up). So I
think the Head Gasket is OK. Power & delivery also seem OK.

My current thoughts now are:
1. Top Hose delaminated inside acting like a diaphram when
pump is running
2. Bottom Hose as per 1.
3. Water Pump knackered.

When water pumps fail would you normally expect external visible signs
(water leaks)? Or does the impeller corrode away such that it cant
move water about??

All my earth straps seem good, nothing else electrical is playing up.

What do you think to be the most likely of above? Or have I missed
something else? I am pretty sure it is not air locked!

Thanks
Jon

dodgy sender switch?

Icky
"Jon" <[email protected]> wrote in message
news:[email protected]...
> Hi all,
>
> A while ago now I posted re my 200tdi, 150k miles running hot (3/4 way
> accross on the gauge).
>
> Upshot was that I replaced knackered radiator, thermostat and viscous
> coupling. This made it so that the vehicle (90) would run all day at
> about 3/4 of the temperature guage without rising when working hard.
>
> This weekend the needle started to venture towards the red so Im back
> pondering the options to return the needle to where it should be
> (about 1/2 way).
>
>
> I still have no signs of water in my oil or oil in my water. It
> doesnt seem to use a drop of water (never have to top it up). So I
> think the Head Gasket is OK. Power & delivery also seem OK.
>
> My current thoughts now are:
> 1. Top Hose delaminated inside acting like a diaphram when
> pump is running
> 2. Bottom Hose as per 1.
> 3. Water Pump knackered.
>
> When water pumps fail would you normally expect external visible signs
> (water leaks)? Or does the impeller corrode away such that it cant
> move water about??
>
> All my earth straps seem good, nothing else electrical is playing up.
>
> What do you think to be the most likely of above? Or have I missed
> something else? I am pretty sure it is not air locked!
>
> Thanks
> Jon
>

In message <[email protected]>
Jon <[email protected]> wrote:

> Hi all,
>
> A while ago now I posted re my 200tdi, 150k miles running hot (3/4 way
> accross on the gauge).
>
> Upshot was that I replaced knackered radiator, thermostat and viscous
> coupling. This made it so that the vehicle (90) would run all day at
> about 3/4 of the temperature guage without rising when working hard.
>
> This weekend the needle started to venture towards the red so Im back
> pondering the options to return the needle to where it should be
> (about 1/2 way).
>
>
> I still have no signs of water in my oil or oil in my water. It
> doesnt seem to use a drop of water (never have to top it up). So I
> think the Head Gasket is OK. Power & delivery also seem OK.
>
> My current thoughts now are:
> 1. Top Hose delaminated inside acting like a diaphram when
> pump is running
> 2. Bottom Hose as per 1.
> 3. Water Pump knackered.
>
> When water pumps fail would you normally expect external visible signs
> (water leaks)? Or does the impeller corrode away such that it cant
> move water about??
>
> All my earth straps seem good, nothing else electrical is playing up.
>
> What do you think to be the most likely of above? Or have I missed
> something else? I am pretty sure it is not air locked!
>
> Thanks
> Jon
>

Your water pump theory sounds plausible. If the bearings fail then
you would expect to see water dribbling out of the little hole
in the underside of housing, but it has been reported that the
impeller can become corroded/fall off such that no water gets pumped.

Richard
--
www.beamends-lrspares.co.uk [email protected]
Running a business in a Microsoft free environment - it can be done
Powered by Risc-OS - you won't get a virus from us!!
Helping keep Land Rovers on and off the road to annoy the Lib Dems

On Mon, 23 May 2005 12:19:34 +0000 (UTC), beamendsltd
<[email protected]> wrote:


>
>Your water pump theory sounds plausible. If the bearings fail then
>you would expect to see water dribbling out of the little hole
>in the underside of housing, but it has been reported that the
>impeller can become corroded/fall off such that no water gets pumped.
>

How can I check the water pump? Presumably it is just a case of
taking the top hose off the radiator (giving it to someone else to
hold) while I turn the engine over! - If it throws water out then its
good I presume??

I suspect these things either work or they dont, with no in-between?

Thanks
jon

In message <[email protected]>
Jon <[email protected]> wrote:

> On Mon, 23 May 2005 12:19:34 +0000 (UTC), beamendsltd
> <[email protected]> wrote:
>
>
> >
> >Your water pump theory sounds plausible. If the bearings fail then
> >you would expect to see water dribbling out of the little hole
> >in the underside of housing, but it has been reported that the
> >impeller can become corroded/fall off such that no water gets pumped.
> >
>
> How can I check the water pump? Presumably it is just a case of
> taking the top hose off the radiator (giving it to someone else to
> hold) while I turn the engine over! - If it throws water out then its
> good I presume??
>

Feeling for pressure in the top hose after the thermostat has opened
also tells you that water is on the move (It warms up quite quickly
once the thermostat opens and pressurises noticably).

> I suspect these things either work or they dont, with no in-between?
>

Thats difficult to say - if the corroded impellor story is true
(I've not seen one) then they can half-work!

> Thanks
> jon

Richard


--
www.beamends-lrspares.co.uk [email protected]
Running a business in a Microsoft free environment - it can be done
Powered by Risc-OS - you won't get a virus from us!!
Helping keep Land Rovers on and off the road to annoy the Lib Dems

On Mon, 23 May 2005 16:21:11 +0000 (UTC), beamendsltd
<[email protected]> wrote:

Ok, so I suspect I should replace the top and bottom hoses and
possibly sender unit first.

Whilst the top hose is off, take out thermostat and check to see if
the pump is pumping.

Then, fail in all that do the Head Gasket.

Does this sound like a sensible approach??

Thanks Jon


>>
>
>Feeling for pressure in the top hose after the thermostat has opened
>also tells you that water is on the move (It warms up quite quickly
>once the thermostat opens and pressurises noticably).
>
>> I suspect these things either work or they dont, with no in-between?
>>
>
>Thats difficult to say - if the corroded impellor story is true
>(I've not seen one) then they can half-work!
>
>> Thanks
>> jon
>
>Richard

In message <[email protected]>
Jon <[email protected]> wrote:

> On Mon, 23 May 2005 16:21:11 +0000 (UTC), beamendsltd
> <[email protected]> wrote:
>
> Ok, so I suspect I should replace the top and bottom hoses and
> possibly sender unit first.
>
> Whilst the top hose is off, take out thermostat and check to see if
> the pump is pumping.
>
> Then, fail in all that do the Head Gasket.
>
> Does this sound like a sensible approach??
>
> Thanks Jon
>
>

If you have a local garage that can test emissions for a
blown head gasket that would perhaps be a better bet, at least
to start with.

Richard

> >>
> >
> >Feeling for pressure in the top hose after the thermostat has opened
> >also tells you that water is on the move (It warms up quite quickly
> >once the thermostat opens and pressurises noticably).
> >
> >> I suspect these things either work or they dont, with no in-between?
> >>
> >
> >Thats difficult to say - if the corroded impellor story is true
> >(I've not seen one) then they can half-work!
> >
> >> Thanks
> >> jon
> >
> >Richard
>

--
www.beamends-lrspares.co.uk [email protected]
Running a business in a Microsoft free environment - it can be done
Powered by Risc-OS - you won't get a virus from us!!
Helping keep Land Rovers on and off the road to annoy the Lib Dems

>
>If you have a local garage that can test emissions for a
>blown head gasket that would perhaps be a better bet, at least
>to start with.
>
>Richard
>

I didnt know this was possisble. Good idea. I will investigate local
garages.
Jon

Ok, I had another better look last night and I fel a bit of a fool...

After my adventures at Driffield the other weekend I pressure washed
the front of the radiator (after remoiving the grill). I assumed that
the pressure washer would remove ALL the crud from between the cooing
fins from front to back - BIG mistake!

Whilst the front of my radiator looks like new the rear looks like a
mud wall and I suspect my immediate problem!

Tonight I will remove the cowling, intercooler (cos thats crudded up
too) and top hose and get the pressure washer around the back.

This should then revert my temperature back to running hot rather than
too hot. Then at the weekend its off to the local garage to get a gas
and pressure test done of the head because I would like to see it
running at 1/2 temperature rather than 3/4.

I'll let you all know how it goes.

Thanks
Jon